How can He decide anything for you except that which is good...
How can He decide anything for you except that which is good, and He is your Maker and Creator. The phrase, "your Creator", points to a special relation which they have with Him, and it emphasizes the fact that the given command is not for revenge; it is based on divine love, in order to purify them.
QUR’?N: that is best for you with your Creator: This and the preceding verses (that enumerate their transgressions and sins) are addressed to the whole Jewish nation, although the sins were committed by only some groups of them and not by all. Obviously it is because they were very much united as a nation; if one did a thing, others were pleased with it. It was because of this feeling of their national unity that one group's action is attributed to the whole nation.
Otherwise, not all the Israelites had killed the prophets, nor had all of them indulged in the calf-worship, or committed other sins mentioned herein. It proves that the order, "kill your people", actually meant, kill some of your people, i.e., the calf-worshippers. It may also be inferred from the words, "you have surely been unjust to yourselves by taking the calf for worship", and the words, "that is best for you with your Creator" (which apparently is the final part of the speech of Mûsâ).
The words, "so He turned to you (mercifully)", prove that their repentance was accepted. Tradition says that their repentance was accepted and sin forgiven when only a few of them had been killed. This forgiveness before the order was fully complied with shows that the command was given as a trial. The case is somewhat similar to the dream of Ibrâhîm (a.s.) and his being told to sacrifice Ismâ’î1; before he could reach the ultimate stage, he was told, O Ibrâhîm!
You have indeed made the vision come true (37 :104 -105) . Likewise, Mûsâ (a.s.) told his people "turn to your Creator (penitently) and kill your people, that is best for you with your Creator", and Allâh confirmed the order, yet He took the killing of some as equal to the execution of all, and informed them that their repentance was accepted, "so He turned to you (mercifully)". QUR’?N: a pestilence from heaven: "ar-Rijz" ( = punishment) .
QUR’?N: do not act corruptly: "Lâ ta'thaw" () is derived from al-`ayth and al-`athy () it means the biggest chaos and mischief. QUR’?N: and its cucumbers and its garlic: "al-Khiyar" () is cucumber; "al-fum" () is garlic or wheat. QUR’?N: and they returned with Allâh's wrath: "Bâ'û" ( = they returned).